TOYOTA AVALON 2001 Service Repair Manual

- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-317
473 Author
: Date
:
2001 AVALON (RM808U)
DTC Normal Code Malfunction in ECM
CIRCUIT DESCRIPTION
If any trouble occurs in the ECM control system, the ECU prohibits ABS & VSC control.
DTC No.DTC Detecting ConditionTrouble Area
Normal Code
Conditions 1., 2,. 3, or 4,continue for 5 sec. or more:
1. Engine malfunction signal is sent from ECM.
2. Shift malfunction signal is sent from ECM
3. The shift position is other than P and N range input volt-
age is 8 V or more.
4. The shift position is PN or rev and D range input voltage
is 8 V or more.
ECM circuit

ECM

Brake fluid level

Brake fluid level warning switch circuit

Steering angle sensor

ABS & BA & TRAC & VSC ECU
INSPECTION PROCEDURE
1 Is DTC out put for ECM?
Check DTC on page DI-3.
YES Repair engine control system according to the
output code.
NO
2 Check the DTC for the ABS and VSC (See page DI-252).
*1 Repair ABS and VSC control system according
to the code output.
*2
Check and replace translate ECU.
*1: Output NG code except for DTC of VSC system C1301/42
*2: Output NG code DTC of VSC system C1301/42 only
DI6OF-03

F09822
ABS & BA &
TRAC & VSC ECU
IND A2031
V V18
IL1 M6 M69
4SLIP
R-B J/B No. 4
4D
4F 413
R-B
Driver Side J/B
1G1
1D10
1B1C 3 41 2IG1 Relay GAUGE
No. 1
W
W-R
2
IG1
AM1 4Ignition Switch
IF17
W-L
551
2 AM1 Engine Room R/B No. 5
B
2G
2H1 1 Engine Room J/B
B-L
F6 1 F10 F81
1
ALT FL Block
IG
Battery
FL MAIN
B Multi Display
4 3
W-BW-L
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-333
489 Author
: Date
:
2001 AVALON (RM808U)
SLIP Indicator Light Circuit
CIRCUIT DESCRIPTION
The SLIP indicator light blinks during TRAC & VSC operation.
WIRING DIAGRAM
DI6OL-03

DI-334
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
490 Author
: Date
:
2001 AVALON (RM808U)
INSPECTION PROCEDURE
HINT:
Start the inspection from step 1, in case of using the TOYOTA hand-held tester and start from step 2, in case
of not using the TOYOTA hand-held tester.
1 Check operation of the SLIP indicator light.
PREPARATION:
(a) Connect the TOYOTA hand-held tester to the DLC3.
(b) Turn the ignition switch ON and push the TOYOTA hand-held tester main switch ON.
(c) Select the ACTIVE TEST mode on the TOYOTA hand-held tester.
CHECK:
Check that ºONº and ºOFFº of the SLIP indicator light can be shown on the combination meter with the TOY-
OTA hand-held tester.
OK Go to step 4.
NG
2 Check that the SLIP indicator light is ON for 3 seconds immediately after ignition
switch is turned ON.
OK Check and replace ABS & BA & TRAC & VSC
ECU.
NG
3 Check SLIP indicator light.
See combination meter troubleshooting on page BE-2.
NG Repair or replace combination meter. Check
and replace ABS & BA & TRAC & VSC ECU.
OK

- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-335
491 Author
: Date
:
2001 AVALON (RM808U)
4 Check for open and short circuit in harness and connector between ABS & BA
TRAC & VSC ECU and SLIP indicator light (See page IN-30).
NG Repair or replace harness or connector.
OK
Check and replace ABS & BA & TRAC & VSC
ECU.

F09806
ABS & BA &
TRAC & VSC ECU
A20 E1
EB
T5TC 84
LG-R
4A
4B 4H
4A6
19
196 LG-R
LG-R
LG-R 21
TC Translate ECU
W-B311LG-R D1
DLC1
TC22
II2 3A 3G4 13
LG-R D2
DLC2
E1 TC
4J/B No. 3 J/B No. 4
F10163
DLC2
Tc E
1DLC1
TcON
DI-342
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
498 Author
: Date
:
2001 AVALON (RM808U)
Tc Terminal Circuit
CIRCUIT DESCRIPTION
Connecting between terminals Tc and E1 of the DLC1 or the DLC2 causes the ECU to display DTC by blink-
ing the ABS warning light, VSC warning light and BRAKE warning light.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check voltage between terminals Tc and E1.
CHECK:
(a) Turn the ignition switch ON.
(b) Measure the voltage between terminals Tc and E
1 of or
DLC1 or terminal Tc of DLC2 and body ground.
OK:
Voltage: 10 - 14 V
OK If each warning light does not blink even after Tc
and E
1 are connected, the ECU may be defec-
tive.
NG
DI6OO-01

- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-343
499 Author
: Date
:
2001 AVALON (RM808U)
2 Check for open and short circuit in harness and connector between ABS & BA &
TRAC & VSC ECU and DLC2 or DLC1, DLC2 or DLC1 and body ground (See page
IN-30).
NG Repair or replace harness or connector.
OK
Check and replace ABS & BA & TRAC & VSC
ECU.

F09808
ABS & BA &
TRAC & VSC ECU
A20TS 42
LG-B
4A
4B4A J/B No. 4
3
12
12 LG-B
LG-B LG-B
II2 11
16 3TS
D1
DLC1
EBW-B
T524
TS Translate ECU D3
DLC3
E1 TSLG-B LG-B
14
AB0119S08096
F00446
Ts
DLC1Ts
DLC1Ts
DLC1Ts
DLC1Ts
DLC1 ONTs
DLC1 E
1
DI-344
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
500 Author
: Date
:
2001 AVALON (RM808U)
Ts Terminal Circuit
CIRCUIT DESCRIPTION
The sensor check circuit detects abnormality in the speed sensor signal which cannot be detected with the
DTC check.
Connecting terminals Ts and E
1 of the DLC1 starts the check.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check voltage between terminals Ts and E1 of DLC1.
CHECK:
(a) Turn the ignition switch ON.
(b) Measure the voltage between terminals Ts and E
1 of
DLC1.
OK:
Voltage: 10 - 14 V
OK If ABS warning light does not blink even after Ts
and E
1 are connected, the ECU may be defec-
tive.
NG
DI6OP-03

- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-345
501 Author
: Date
:
2001 AVALON (RM808U)
2 Check for open and short circuit in harness and connector between ABS & BA &
TRAC & VSC ECU and DLC1, DLC1 and body ground (See page IN-30).
NG Repair or replace harness or connector.
OK
Check and replace ABS & BA & TRAC & VSC
ECU.

F09811
Battery
FL MAIN
B F61 F10 F81
1
ALT
FL
BlockB-L
2G
2H1 1 5
5 1 2AM1 Engine Room R/B No. 5
Engine Room J/BB W-LW-L
IF17 W-R
2
IG1 AM1 4Ignition Switch WDriver Side J/B
1G1
1B 13
1B3
1C4
3
4 12 IG1 RelayECU-IG
No. 2
W-B
IG Y-R
L-WABS & BA &
TRAC & VSC ECU
A20 V9
VSC Warning
Buzzer
BZ 86
Buzzer1 2
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-339
495 Author
: Date
:
2001 AVALON (RM808U)
VSC Buzzer Circuit
CIRCUIT DESCRIPTION
The VSC buzzer sounds during VSC operation.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Start the inspection from step 1 in case of using the TOYOTA hand-held tester and start from step 3 in case
of not using the TOYOTA hand-held tester.
1 Check operation of the VSC buzzer.
PREPARATION:
(a) Connect the TOYOTA hand-held tester to the DLC3.
(b) Turn the ignition switch ON and push the TOYOTA hand-held tester main switch ON.
(c) Select the ACTIVE TEST mode on the TOYOTA hand-held tester.
CHECK:
Check ºON-OFFº function of the VSC buzzer with the TOYOTA hand-held tester.
OK Check and replace ABS & BA & TRAC & VSC
ECU.
NG
DI6ON-03

F02192
1
2 (+) (-)
DI-340
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
496 Author
: Date
:
2001 AVALON (RM808U)
2 Check voltage between terminal 1 of VSC buzzer and body ground.
PREPARATION:
Disconnect the connector from VSC buzzer.
CHECK:
(a) Turn the ignition switch ON.
(b) Measure voltage between terminal (1) of VSC buzzer and body ground.
OK:
Voltage: 10 - 14 V
NG Repair or replace harness or connector from
voltage supply to VSC buzzer.
OK
3 Check VSC buzzer.
PREPARATION:
Disconnect the VSC buzzer connector.
CHECK:
Apply battery positive voltage to the terminals 1 and 2 of VSC
buzzer connector, and check that the VSC buzzer sounds.
NG Replace VSC buzzer.
OK